1. Field of the Invention
The present invention relates to a method of manufacturing a wiring board, from an end face of which flying leads project, and the wiring board.
2. Description of the Related Art
A semiconductor apparatus in which flying leads projecting from an end face of a wiring board are bonded to bonding electrodes disposed in a row in a semiconductor chip is widely used. In a micro semiconductor chip, a plurality of bonding electrodes are disposed in a row at a narrow pitch.
When flying leads are arrayed at a narrow pitch according to the array pitch of the bonding electrodes, it is likely that the flying leads are short-circuited. In a wiring board on which conductor wires are manufactured by etching of copper foil or the like, to reduce a pitch, an etching technique for forming gaps with extremely high accuracy and a high aspect ratio is necessary. That is, manufacturing of a wiring board including narrow-pitch flying leads is not easy.
Japanese Patent Application Laid-Open Publication No. 2008-235791 discloses a semiconductor apparatus in which portions triangular in a sectional shape and portions square in a sectional shape are manufactured in conductor wires of a wiring board and the portions triangular in the sectional shape of the conductor wires are machined into flying leads and bonded to bonding electrodes of a semiconductor chip.